An example of a technique that is of interest for the present disclosure is described in Japanese Patent No. 4184394. FIGS. 8, 9, and 10, which are cited from Japanese Patent No. 4184394, respectively correspond to FIGS. 2, 4, and 5 in Japanese Patent No. 4184394. FIGS. 8 to 10 depict the following components: a flange 1, which constitutes a part of a core included in a coil component, a terminal electrode 2 positioned on the flange 1, and an end portion of a wire 3 connected to the terminal electrode 2.
As illustrated in FIGS. 8 and 10, the wire 3 includes a central conductor 4 having a substantially linear shape, and an insulating coating layer 5 that covers the peripheral surface of the central conductor 4. The terminal electrode 2 has a base 7, and a receiving part 9. The base 7 is positioned on the same side as an outer end face 6 of the flange 1. The receiving part 9 extends from the base 7 via a bending part 8, and receives an end portion of the wire 3. The terminal electrode 2 further includes a welding part 11, and a holding part 13. The welding part 11 extends from the receiving part 9 via a first fold-back part 10, and is to be welded to the central conductor 4 of the wire 3. The holding part 13 extends from the receiving part 9 via a second fold-back part 12 to hold and position the wire 3 in place.
The state of the welding part 11 prior to undergoing a welding step, and the state of the welding part 11 after undergoing the welding step are respectively illustrated in FIG. 8 and FIGS. 9 and 10. A weld ball 14 formed as a result of this welding is illustrated in FIGS. 9 and 10.
The welding step is performed as follows. Prior to the welding step, the welding part 11 and the holding part 13 of the terminal electrode 2 are in their unfolded state with respect to the receiving part 9, and are not facing the receiving part 9. FIG. 8 depicts a state in which, although the holding part 13 is facing the receiving part 9, the welding part 11 is in its unfolded state with respect to the receiving part 9.
First, the wire 3 is placed on the receiving part 9 of the terminal electrode 2. To temporarily secure the wire 3 in this state, the holding part 13 is folded toward the receiving part 9 at the second fold-back part 12 such that the wire 3 becomes sandwiched between the receiving part 9 and the holding part 13.
Next, as illustrated in FIG. 8, the insulating coating layer 5 is removed in the portion of the wire 3 located closer to the distal end of the wire 3 relative to the holding part 13. At this time, for example, laser beam irradiation is employed to remove the insulating coating layer 5. As clearly depicted also in FIG. 10, the portion of the insulating coating layer 5 in contact with the receiving part 9 is allowed to remain unremoved.
Next, the welding part 11 is folded toward the receiving part 9 at the first fold-back part 10, causing the wire 3 to become sandwiched between the welding part 11 and the receiving part 9.
Next, the central conductor 4 of the wire 3 and the welding part 11 are welded together. More specifically, laser welding is performed. A laser beam is applied to the welding part 11, causing the central conductor 4 of the wire 3 and the welding part 11 to melt into each other, thus welding the central conductor 4 and the welding part 11 together.